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panic: kernel diagnostic assertion "rn != NULL" failed: file "/syzkaller/managers/multicore/kernel/sys/net/pipex.c", line 459
Starting stack trace...
panic(ffffffff833ab136) at panic+0x1d0 sys/kern/subr_prf.c:229
__assert(ffffffff833ee48c,ffffffff8340ba49,1cb,ffffffff833a8c27) at __assert+0x29 sys/kern/subr_prf.c:-1
pipex_unlink_session_locked(ffff80002a362ec8) at pipex_unlink_session_locked+0x409
pipex_destroy_all_sessions(ffff8000014de800) at pipex_destroy_all_sessions+0xd9 pipex_rele_session sys/net/pipex.c:-1 [inline]
pipex_destroy_all_sessions(ffff8000014de800) at pipex_destroy_all_sessions+0xd9 sys/net/pipex.c:151
pppacclose(637e,81,2000,ffff80002a272010) at pppacclose+0x16f sys/net/if_pppx.c:1335
spec_close(ffff80003c41e510) at spec_close+0x417 sys/kern/spec_vnops.c:-1
VOP_CLOSE(fffffd805f9a1510,81,fffffd80097fd2d8,ffff80002a272010) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156
vn_closefile(fffffd8060537a00,ffff80002a272010) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline]
vn_closefile(fffffd8060537a00,ffff80002a272010) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615
fdrop(fffffd8060537a00,ffff80002a272010) at fdrop+0x121 sys/kern/kern_descrip.c:1280
closef(fffffd8060537a00,ffff80002a272010) at closef+0x192 sys/kern/kern_descrip.c:1264
fdfree(ffff80002a272010) at fdfree+0x116 sys/kern/kern_descrip.c:1195
exit1(ffff80002a272010,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215
sys_exit(ffff80002a272010,ffff80003c41e880,ffff80003c41e7d0) at sys_exit+0x1a sys/kern/kern_exit.c:-1
syscall(ffff80003c41e880) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80003c41e880) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:775
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x6f93271b2600, count: 242
End of stack trace.
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